While it’s not formulaic compared to the other anime, it is pretty formulaic to itself. Each season is watching to see what horror the MC has to face and what he does to eventually overcome it all while dying and/or watching his friends die in brutal and creative ways.

Having said that, I do enjoy the anime, the characters feel pretty unique compared to other anime and the dialogue is very different. Those writers are very good at doing batshit insane monologues